Malaysian Journal of Analytical Sciences最新文献

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PHOTOCATALYTIC DEGRADATION OF PHENOL DERIVATIVES OVER SILVER SUPPORTED ON MESOPOROUS TITANIA NANOPARTICLES 介孔二氧化钛纳米粒子负载银催化降解苯酚衍生物
Malaysian Journal of Analytical Sciences Pub Date : 2018-10-25 DOI: 10.17576/mjas-2018-2205-08
Malaysian Journal, Degradasi Fotomangkinan, Terbitan Fenol, Ke Atas Perak, Berliang Meso, N. F. Jaafar, A. A. Jalil
{"title":"PHOTOCATALYTIC DEGRADATION OF PHENOL DERIVATIVES OVER SILVER SUPPORTED ON MESOPOROUS TITANIA NANOPARTICLES","authors":"Malaysian Journal, Degradasi Fotomangkinan, Terbitan Fenol, Ke Atas Perak, Berliang Meso, N. F. Jaafar, A. A. Jalil","doi":"10.17576/mjas-2018-2205-08","DOIUrl":"https://doi.org/10.17576/mjas-2018-2205-08","url":null,"abstract":"In this study, the potential of silver supported on mesoporous titania nanoparticles (Ag-MTN) as visible-light-driven photocatalyst was investigated for the degradation of phenol derivatives. Characterisation results illustrated that the presence of Ag reduced the band gap of MTN and increased the number of oxygen vacancies (OV) and Ti site defect (TSD). The presence of both properties is among the important factors that need to be considered for catalyst properties in order to achieve effective photocatalytic degradation under visible light. The photoactivity of the catalyst was also significantly influenced by the presence of Ag, which acted as an electron trap that enhanced electron-hole separation. The ability of Ag-MTN to degrade phenol derivatives [phenol (Ph), 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-diCP), and 4-acetamidophenol (4-AcePh)] was compared with commercial TiO2 and MTN. The percentage degradation of phenol derivatives was in the following order: TiO2 < MTN < Ag-MTN. This indicated that the presence of Ag in MTN effectively enhanced the photoactivity of MTN towards the degradation of phenol derivatives.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43972219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
IMMOBILIZED METAL AFFINITY CHROMATOGRAPHIC MEMBRANE FOR TRYPSIN SEPARATION 用于胰蛋白酶分离的固定化金属亲和层析膜
Malaysian Journal of Analytical Sciences Pub Date : 2018-10-25 DOI: 10.17576/mjas-2018-2205-13
S. Hamzah, Nurul Hidayati Mat Alim, Nurul Fakhriah Ismail, N. Yatim, N. A. Sani
{"title":"IMMOBILIZED METAL AFFINITY CHROMATOGRAPHIC MEMBRANE FOR TRYPSIN SEPARATION","authors":"S. Hamzah, Nurul Hidayati Mat Alim, Nurul Fakhriah Ismail, N. Yatim, N. A. Sani","doi":"10.17576/mjas-2018-2205-13","DOIUrl":"https://doi.org/10.17576/mjas-2018-2205-13","url":null,"abstract":"As a new technology, Immobilized Metal Affinity Chromatographic Membrane (IMAC) has proven its efficiency for protein purification. It is also a separation technique that use covalently bound chelating compounds on the membrane supports to immobilize metal ions, which serve as affinity ligands for various proteins. This study aims to prepare and characterize highly specific IMAC for trypsin separation. Chitosan and polyethylene glycol were used as modification solutions to impart the membrane porosity and flux recovery ratio (FRR) of IMAC matrix. The modified PSf with chitosan improved its FRR up to 82.11% which indicated that PSf/Chitosan was a suitable matrix for the affinity membrane. Glutaraldehyde and Cu served as crosslinker agents and affinity ligands respectively. Maximum immobilization capacity of Cu occurred at 120 ppm within 60 minutes’ incubation time. The optimum capacity of trypsin adsorption (12.67 mg/cm) onto IMAC membrane occurred when 0.3 M ionic strength of trypsin solution was used. Desorption of the enzyme by displacing salt of potassium chloride showed the highest trypsin recovery at 72.3%.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44676058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
LIQUID CHROMATOGRAPHY TANDEM MASS SPECTROMETRY FOR THE DETECTION AND VALIDATION OF QUERCETIN-3-O-RUTINOSIDE AND MYRICETIN FROM FRACTIONATED Labisia pumila var. alata 液相色谱-串联质谱法检测和验证浮木中槲皮素-3-邻RUTINOSIDE和MYRICETIN
Malaysian Journal of Analytical Sciences Pub Date : 2018-10-25 DOI: 10.17576/mjas-2018-2205-09
{"title":"LIQUID CHROMATOGRAPHY TANDEM MASS SPECTROMETRY FOR THE DETECTION AND VALIDATION OF QUERCETIN-3-O-RUTINOSIDE AND MYRICETIN FROM FRACTIONATED Labisia pumila var. alata","authors":"","doi":"10.17576/mjas-2018-2205-09","DOIUrl":"https://doi.org/10.17576/mjas-2018-2205-09","url":null,"abstract":"","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48659392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 5
PHYSICOCHEMICAL CHARACTERISTICS OF RECYCLED TYRE TREAD COMPOUNDS 再生轮胎胎面胶的物理化学特性
Malaysian Journal of Analytical Sciences Pub Date : 2018-10-25 DOI: 10.17576/mjas-2018-2205-05
Malaysian Journal, Ciri-Ciri Fizik-kimia, Sebatian bagi Bunga, Tayar Kitar Semula, M. Abbas, A. Zaini, A. Arsad, Z. Zakaria, Azhar Abdollah, Z. A. Wahid
{"title":"PHYSICOCHEMICAL CHARACTERISTICS OF RECYCLED TYRE TREAD COMPOUNDS","authors":"Malaysian Journal, Ciri-Ciri Fizik-kimia, Sebatian bagi Bunga, Tayar Kitar Semula, M. Abbas, A. Zaini, A. Arsad, Z. Zakaria, Azhar Abdollah, Z. A. Wahid","doi":"10.17576/mjas-2018-2205-05","DOIUrl":"https://doi.org/10.17576/mjas-2018-2205-05","url":null,"abstract":"The present work was aimed at evaluating the physicochemical characteristics of seven recycled tyre tread compounds. The materials were characterized for elemental composition, surface morphology, surface chemistry, oil content, ash content, thermal degradation and dielectric properties. Some of the materials were analyzed according to the Rubber Research Institute Malaysia (RRIM) in-house methods for comparison. Natural rubber, butadiene rubber and styrene-butadiene rubber were also employed to validate the thermal degradation profile. Results show that all materials exhibit comparable elemental composition, and dielectric and surface properties, but dissimilar composition of rubber compounds as revealed by the simple mass balancethermogravimetric approach. The finding is consistent with the RRIM in-house methods. The proposed thermogravimetric approach is sufficient to assess the composition and quality of recycled tyre tread compounds.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48494479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
TOTAL FLAVONOIDS AND PHENOLIC CONTENTS OF STICKY AND HARD PROPOLIS FROM 10 SPECIES OF INDO-MALAYAN STINGLESS BEES 10种印度-马来亚无刺蜂粘性和硬蜂胶总黄酮和酚类含量
Malaysian Journal of Analytical Sciences Pub Date : 2018-10-25 DOI: 10.17576/mjas-2018-2205-15
Malaysian Journal, N. Awang, F. Majid, S. Hamzah, B. A. Razak
{"title":"TOTAL FLAVONOIDS AND PHENOLIC CONTENTS OF STICKY AND HARD PROPOLIS FROM 10 SPECIES OF INDO-MALAYAN STINGLESS BEES","authors":"Malaysian Journal, N. Awang, F. Majid, S. Hamzah, B. A. Razak","doi":"10.17576/mjas-2018-2205-15","DOIUrl":"https://doi.org/10.17576/mjas-2018-2205-15","url":null,"abstract":"The present works aimed to identify the total flavonoids content (TFC), total phenolic content (TPC) and antioxidant activities of sticky and hard propolis of 10 species of Indo-Malayan stingless bee’s namely Heterotrigona itama (H. itama), Geniotrigona thoracica (G. thoracica), Homotrigona aliceae (H. aliceae), Homotrigona fimbriata (H. fimbriata), Tetrigona apicalis (T. apicalis), Tetrigona vidua (T. vidua), Tetrigona peninsularis (T. peninsularis), Lophotrigona canifrons (L. canifrons), Tetrigona melanoleuca (T. melanoleuca), and Tetrogona binghami (T. binghami). The ethanolic extracts of these propolis (EEP) were prepared and analysed for the determination of TFC using aluminium chloride method, TPC and antioxidant activity using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging assay system. The sticky propolis showed 91% of TFC and 49% of TPC higher than the hard propolis. Interestingly, the sticky propolis had stronger antioxidant activities than hard propolis for all species. The highest antioxidant activities were found in sticky propolis of H. itama which is 85% of DPPH degradation while the lowest antioxidant activity was found in the hard propolis of L. conifrons which is 5% of DPPH degradation. In conclusion, the data gathered in this study revealed that propolis from all 10 types of stingless bees’ species are biologically active. The selection of propolis for further development can be based on its biological activities, which vary according to the species of stingless bees.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41612251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 14
SEPARATION OF L-ARGININE AND L-CITRULLINE IN RED AND YELLOW CRIMSON WATERMELON (Citrullus lanatus) JUICES EXTRACT USING HPLC GRADIENT MODE 高效液相色谱梯度法分离红、黄西瓜汁中L-精氨酸和L-瓜氨酸
Malaysian Journal of Analytical Sciences Pub Date : 2018-10-01 DOI: 10.17576/MJAS-2018-2205-06
R. Ridwan, A. R. H. Rashmizal, M. Adenan, M. Mazlina
{"title":"SEPARATION OF L-ARGININE AND L-CITRULLINE IN RED AND YELLOW CRIMSON WATERMELON (Citrullus lanatus) JUICES EXTRACT USING HPLC GRADIENT MODE","authors":"R. Ridwan, A. R. H. Rashmizal, M. Adenan, M. Mazlina","doi":"10.17576/MJAS-2018-2205-06","DOIUrl":"https://doi.org/10.17576/MJAS-2018-2205-06","url":null,"abstract":"Watermelon (Citrullus lanatus) is a nutritious fruit that has attracted scientific interest due to its phytonutrient content including carotenoids and amino acids. Watermelon juice is the richest known source of amino acids including L-arginine and L-citrulline. For a complete separation of amino acids in watermelon juices, a gradient mode of reverse phase high performance liquid chromatography (RP-HPLC) with UV detection was utilised owing to its supremacy over isocratic mode. This present study was aimed at achieving good separation of chromatography profiles and baseline between L-arginine and L-citrulline in red and yellow crimson watermelon juice extract. The edible parts of watermelons were juiced, stored at – 80 C and freeze dried to obtain dried juice powder. Samples were analysed by gradient mode of RP-HPLC using 0.1% orthophosphoric acid in water (v/v) and acetonitrile as mobile phase A and B. The chromatograph separation was performed using Gemini C18 column at a flow rate of 1.0 mL/min, maintained temperature at 25 C while detection was made at four different wavelengths; 195 nm, 200 nm, 207 nm and 210 nm with total analysis time of 35 min. Excellent chromatographic separation was achieved at conditions of gradient elution (0%B 95%B, 0-18 minutes and 95%B, 18-23 minutes, 95%B-0%B, 23-25 minutes, 0%B, 25-35 minutes) with baseline between L-arginine and L-citrulline in both watermelon juice extracts. The gradient mode used in this RP-HPLC successfully achieved efficient separation of chromatographic profile for amino acids, L-arginine and L-citrulline in the red and yellow crimson watermelon juice extracts.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41683400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
THE EFFECTS OF GLYCEROL ADDITION TO THE MECHANICAL PROPERTIES OF THERMOPLASTIC FILMS BASED ON JACKFRUIT SEED STARCH 添加甘油对菠萝蜜种子淀粉基热塑性薄膜力学性能的影响
Malaysian Journal of Analytical Sciences Pub Date : 2018-10-01 DOI: 10.17576/mjas-2018-2205-17
N. A. Shahrim, N. Sarifuddin, H. M. Zaki, A. Azhar
{"title":"THE EFFECTS OF GLYCEROL ADDITION TO THE MECHANICAL PROPERTIES OF THERMOPLASTIC FILMS BASED ON JACKFRUIT SEED STARCH","authors":"N. A. Shahrim, N. Sarifuddin, H. M. Zaki, A. Azhar","doi":"10.17576/mjas-2018-2205-17","DOIUrl":"https://doi.org/10.17576/mjas-2018-2205-17","url":null,"abstract":"Thermoplastic films based on 3 wt.% jackfruit seed starch were prepared using 5 to 30 wt.% glycerol as plasticizer via solution \u0000casting method. The aim of this study is to investigate the effect of glycerol on the mechanical properties of films. According to \u0000the analysis, the optimum tensile strength of the film was obtained at 4.40 MPa, which revealed that the native starch granules \u0000were converted into a continuous phase in the presence of glycerol as indicated by scanning electron microscopy. The \u0000incorporation of glycerol in starch also showed the formation of hydrogen bond evidenced by Fourier transform infrared \u0000spectroscopy.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42898494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 6
REMOVAL OF OIL AND GREASE AND ANIONIC SURFACTANTS IN SYNTHETIC CAR WASH WASTEWATER USING KAPOK FIBER: A BATCH-SCALE STUDY 木棉纤维去除合成洗车废水中的油脂和阴离子表面活性剂的批量研究
Malaysian Journal of Analytical Sciences Pub Date : 2018-08-16 DOI: 10.17576/mjas-2018-2204-20
{"title":"REMOVAL OF OIL AND GREASE AND ANIONIC SURFACTANTS IN SYNTHETIC CAR WASH WASTEWATER USING KAPOK FIBER: A BATCH-SCALE STUDY","authors":"","doi":"10.17576/mjas-2018-2204-20","DOIUrl":"https://doi.org/10.17576/mjas-2018-2204-20","url":null,"abstract":"","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46985413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 4
SYNERGISTIC EFFECT OF ADSORPTION-PHOTODEGRADATION OF COMPOSITE TiO2/AC FOR DEGRADATION OF 1-BUTYL-3-METHYLIMIDAZOLIUM CHLORIDE 复合TiO2/AC吸附-光降解降解1-丁基-3-甲基咪唑的协同效应
Malaysian Journal of Analytical Sciences Pub Date : 2018-08-16 DOI: 10.17576/mjas-2018-2204-11
Azhar Zawawi, R. Ramli, N. Y. Harun
{"title":"SYNERGISTIC EFFECT OF ADSORPTION-PHOTODEGRADATION OF COMPOSITE TiO2/AC FOR DEGRADATION OF 1-BUTYL-3-METHYLIMIDAZOLIUM CHLORIDE","authors":"Azhar Zawawi, R. Ramli, N. Y. Harun","doi":"10.17576/mjas-2018-2204-11","DOIUrl":"https://doi.org/10.17576/mjas-2018-2204-11","url":null,"abstract":"Most ionic liquids (ILs) were reported to be highly toxic and non-biodegradable such as ILs with imidazolium type cation. To overcome this problem, degradation of imidazolium based ILs via advance oxidation process is needed. In this research, photocatalytic study was employed in order to study the efficiency of the system for removal of ILs from wastewater. To introduce synergistic effect of adsorption-photodegradation, composite photocatalyst TiO2/AC was synthesized using two steps (1) nano-TiO2 was synthesized using microemulsion method and (2) it deposited onto functionalize (AC) activated carbon using impregnation method. The prepared composite photocatalyst was characterized using Thermo Gravimetric Analyzer (TGA), Brunauer-Emmet-Teller (BET) and Field Emission Scanning Electron Microscopic (FESEM). Photocatalytic study of 1-butyl-3methylimidazolium chloride (bmimCl) was employed under visible light region. Increasing amount of AC as support increased the degradation rate of bmimCl. However, excess AC reduced the removal rate of bmimCl. Composite TiO2/AC with 10 wt.% AC as support shows highest degradation rate with total removal 18.47%. Composite photocatalyst may enhance the diffusion rate between bmimCl and TiO2 surface which increase the efficiency for overall systems.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43986943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 6
ANALYSIS OF AMMONIUM ADSORPTION BEHAVIOR AND MASS TRANSFER RESISTANCE FROM AERATED LAGOON EFFLUENT ONTO ACTIVATED CARBON 活性炭对曝气泻湖出水氨的吸附性能及传质阻力分析
Malaysian Journal of Analytical Sciences Pub Date : 2018-08-16 DOI: 10.17576/mjas-2018-2204-19
{"title":"ANALYSIS OF AMMONIUM ADSORPTION BEHAVIOR AND MASS TRANSFER RESISTANCE FROM AERATED LAGOON EFFLUENT ONTO ACTIVATED CARBON","authors":"","doi":"10.17576/mjas-2018-2204-19","DOIUrl":"https://doi.org/10.17576/mjas-2018-2204-19","url":null,"abstract":"","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41376160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
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